764 FXUS64 KHGX 091139 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 639 AM CDT Tue Apr 9 2019 .AVIATION... VFR with light W to NW winds in the morning gradually becoming more SW to S later this afternoon and especially overnight. We will be watching for possible fog and/or low clouds mainly during the late night through early morning hours. S winds will be increasing and becoming gusty during the day tomorrow. 45 && .PREV DISCUSSION... /ISSUED 347 AM CDT Tue Apr 9 2019/ DISCUSSION... Quiet weather is expected for the rest of the work week. A weak front may droop into the area on Thursday, but will be hard pressed to generate anything beyond a brief wind shift and only the slightest bit of cooling. The next chance for rain and storms will come this weekend as a coastal trough develops in the remnants of that weak front, and lifts north/northeast this weekend. Until then, the major story will be temperatures over the next couple of days that are more reminiscent of May than April. NEAR TERM [Through Today]... Clear sky, light winds across Southeast Texas tonight as we sit in a relative flat area of pressure gradient while a low pressure center leaves us behind as it moves from Mississippi into Alabama. Dewpoints are in the upper half of the 50s to around 60 degrees for most everyone, which will allow us to get a bit chillier than we have of late. Despite the low temperature floor, the sky tomorrow will be sunny, and winds are expected to be fairly light. This seems like a great situation for temps to soar, and so my forecast highs for today run at/above the high edge of the guidance envelope. I do have a few 90 degree pixels way down in Jackson County, though I don't know if the odds are very good that we'll see 90 measured anywhere...yet. For all you may hear this week that "Winter Is Coming", it's much more meteorologically accurate to say that "Summer Is Coming", and today's weather will confirm that. SHORT TERM [Tonight Through Thursday]... Despite midlevel ridging being stronger tomorrow, and 850 temps rising above 20C, I have highs a touch cooler Wednesday than today. We'll still have sunny skies, but the main change from today to tomorrow will be that a new low will be deepening rather impressively over the high Central Plains, and give us moderate to gusty onshore winds Wednesday. This will do two things - encourage mixing in the boundary layer, and at least modestly increase low level dewpoints. Both will act to temper the diurnal rise in temperatures, so instead of easy 90s, most places may not even match today's highs. This should be most apparent at the coast, where onshore winds will be most effective in holding back warming. Still...I'm riding pretty close to the high edge of the model guidance. As that impressively deepening low ejects up towards the Western Great Lakes on Thursday, we'll see it drag a cold front all the way down into Texas. But...with the most dynamic part of this spring storm far, far to our north, and moisture return looking anemic (the most optimistic progged precipitable water is not quite 1 1/3 inches...most is lower), don't expect we'll see a real strong boundary making its way into Southeast Texas. We should stay virtually dry, though some real light stuff might get squeezed out just north and east of Galveston Bay. I've conservatively got some slight chance PoPs in place there Thursday afternoon...just in case. LONG TERM [Thursday Night Through Tuesday]... For all that it lacks, this front should manage at least a breath of cold advection, so the back half of the week doesn't look quite as hot as the front half of the week. Highs should be much closer to seasonal averages...give or take a few degrees. As we head towards the weekend though, whatever's left of that old frontal zone may provide a focus for the development of a coastal trough. Meanwhile, another upper trough should be dropping off the Rockies. While it may not be quite as dynamic as the mid-week trough, it does look to dig quite a bit further south, perhaps latching onto the coattails of the lead trough's connection with the subtropical jet. We'll also have more time for low level moisture to surge into the developing surface trough. All in all, things look pretty solid for rain this weekend. There's still some uncertainty in how these multiple elements will shake out, so I flatten PoPs out a bit, stretching from as early as Friday to as late as Sunday...but Saturday will likely be the day to focus on. Of course, this is some time out, but we'll have to monitor this weekend careful for potential to see both severe weather and heavy rains. It is a favorable time of year, and an upper trough/jet running above a coastal trough certainly does catch the eye. It seems to catch SPC's eye, as well - their Day 6 outlook does not have a 15% area over us yet, but they do note that if confidence increases, one may become necessary. The key difference I see at this point is that the GFS keeps decent instability limited to the immediate coastline, while the Euro is more generous over SE Texas. Additionally, the GFS and Euro both have a 40+ knot low level jet feeding into this setup, which is...not exactly something I'd prefer to see. For what it's worth, both the NAEFS and ECMWF Ensembles have 97+ percentile meridional flow, precipitable water, and vapor transport in place on Saturday. Still, this some time off yet, requires multiple pieces to align properly, and we have time to monitor. For now, let's enjoy the fair weather across all of Southeast Texas, and check back in periodically for the latest info on potential for a stormy weekend. MARINE... Light southwest to west winds and low seas can be expected today. Winds will become southerly tonight and increase on Wednesday as low pressure significantly deepens in the western Nebraska area. Caution flags will likely be needed Wednesday afternoon for the increasing winds and building seas, and advisory flags are possible late Wednesday afternoon and on into Wednesday night. Lower south to southeast winds and decreasing seas can be expected Thursday and Thursday night as the pressure gradient weakens, but flags are probably still going to be needed. Friday/Saturday period will see strengthening east winds eventually becoming southeast along with building seas once again as the next storm system organizes out west and eventually works its way across the state over the weekend. There will be increasing rain chances with this storm system, and it currently looks like it will swing a cold front through the area on Saturday night. Caution and/or advisory flags will probably be needed both ahead of and behind the front. 42 HYDROLOGY... One river flood warning remains in effect for the Navasota River near Normangee. The gage at the point has reached flood stage, and continues to rise. Rises should be begin to slow later today. Crest is expected just into moderate flood very late tonight or very early on Wednesday, after which a slow decline in river level will begin. Rises are expected on various other creeks and rivers in the area, and several points are forecast to reach bankfull in the coming days. People will want to use caution near rivers that are running higher and faster than normal. But at this time, no other points are expected to reach into flood stage, though a couple may come close. && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 86 61 87 62 82 / 0 0 0 0 0 Houston (IAH) 88 64 87 65 85 / 0 0 0 0 10 Galveston (GLS) 78 67 77 68 78 / 0 0 0 0 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$